What connectors are allowed for toilet and shower vents

[Hawk73ku]

I made a major blunder stemming from having to rearrange the floorplan for fixtures to fit. Original plan had toilet where the shower is now and the door where the toilet is now. Anyway I was probably so frustrated I got my head up my butt and didn't install a toilet vent and it was pointed out to me that the shower vent was improperly done since it lacks 45° and there is not enough space to get vertical. This is 2nd floor bathroom.

Does IPC allow a sanitary T allowed on a horizontal drain line to connect a vent or must a WYE be used?

 

[Reach4]

You meant "drain line from vanity and tub".

I don't think your "shower vent" is needed, since the shower would be wet vented by the vanity.

 

[Sponsor]

 

[Jeff H Young]

so there is no vent for the lav ? you didnt draw a vent for lav that vent upstream is a horrizontal dry vent below the floor as is the 2 inch vent is illegal under floor as both are dry vents

 

[wwhitney]

Several comments based on the IPC:

- Your diagram is confusing because it appears you are attempting to show 3 dimensions on the page, without any guidance or system for which lines are actually vertical.

- In your picture, it appears you have a 3" drain line running through your joists. For the IRC, the largest prescriptively allowable hole diameter in a joist is 1/3 the joist depth. All holes need to avoid the top and bottom 2" of height of the joist. Holes in joists also must not have any notches above or below them.

If your joists were 2x12 (they look smaller) at 11.25" of depth, then you could drill a 3.75" hole through them for a 3.5" OD 3" DWV pipe, as long as that hole is in the central 7.25" of the joist height. But you have notches below your holes. So the joists with the 3" DWV passing through them will need to be repaired.

- For a bathroom, you always have to dry vent the lavatory (the highest trap in the room) with a vent through the roof or with an AAV. That vent needs to connect to the lavatory trap arm above the floor, within one trap diameter of fall from the trap outlet. Typically via a san-tee in the wall behind the lavatory. So do you have that?

Typically that is the only dry vent you need, as you can wet vent all the other fixtures. The diagram below shows just the underfloor drain piping you would then need, along with the minimum sizes, where green is 1.5", blue is 2", and red is 3". The green line from the vanity is the one that is dry vented above the floor. Note that the tub and the shower trap arms have to be "short enough", meaning that the trap arm may only fall one trap diameter before joining the drain that wet vents the fixture (the drain carrying the lavatory drainage).

- If for some reason you want to dry vent every fixture, let us know and we can answer the actual questions you posted in the OP.

Cheers, Wayne

 

[Jeff H Young]

looks like 2 inch pipe going through joists to me but photo does distort the size

 

[Hawk73ku]

looks like 2 inch pipe going through joists to me but photo does distort the size

You are correct. 2" going through joists.

 

[Hawk73ku]

Several comments based on the IPC:

- Your diagram is confusing because it appears you are attempting to show 3 dimensions on the page, without any guidance or system for which lines are actually vertical.

- In your picture, it appears you have a 3" drain line running through your joists. For the IRC, the largest prescriptively allowable hole diameter in a joist is 1/3 the joist depth. All holes need to avoid the top and bottom 2" of height of the joist. Holes in joists also must not have any notches above or below them.

If your joists were 2x12 (they look smaller) at 11.25" of depth, then you could drill a 3.75" hole through them for a 3.5" OD 3" DWV pipe, as long as that hole is in the central 7.25" of the joist height. But you have notches below your holes. So the joists with the 3" DWV passing through them will need to be repaired.

- For a bathroom, you always have to dry vent the lavatory (the highest trap in the room) with a vent through the roof or with an AAV. That vent needs to connect to the lavatory trap arm above the floor, within one trap diameter of fall from the trap outlet. Typically via a san-tee in the wall behind the lavatory. So do you have that?

Typically that is the only dry vent you need, as you can wet vent all the other fixtures. The diagram below shows just the underfloor drain piping you would then need, along with the minimum sizes, where green is 1.5", blue is 2", and red is 3". The green line from the vanity is the one that is dry vented above the floor. Note that the tub and the shower trap arms have to be "short enough", meaning that the trap arm may only fall one trap diameter before joining the drain that wet vents the fixture (the drain carrying the lavatory drainage).

- If for some reason you want to dry vent every fixture, let us know and we can answer the actual questions you posted in the OP.

Cheers, Wayne

View attachment 107525

Sorry but I'm not a plumber and is why I'm here. That is a 2" pipe going through 2x8 and as an added precaution I've purchased joist repair plates from joistrepair.com which would allow for up to 4" hole in joist. I just haven't installed them yet and believe me I was pretty upset when I opened the ceiling to find 2x8 joists with boards nailed to them to lower the ceiling to accommodate 4" cast iron pipe.

I do have a vanity vent that goes straight up to attic/roof but it's 1.5" if that matters. I can change if need be. I'm not married to work I've done and am looking for best practice from you. I think I used a WYE but will double check.

Sorry about the pictures but I don't know how else to show. Everything shown is horizontal except where dry vents that I many not even need go up. Downsteam of the toilet the line descends to the basement. This is the 2nd floor bathroom. What I show is a 3" drain coming from a WYE just downstream of a 2nd WYE for toilet vent. Upstream near the shower drain I have WYE connecting a 2" drain line which is perpendicular to the 3".

Wet venting all other fixtures? Tell me more. Are you saying I don't even need that shower vent (which I'm told is improper anyway?) And the tub as well? Those fixtures just use the top 1/2 of the drain pipe for vent? I do have a vent for the toilet in the wall behind it. Every toilet I've ever seen is like this but that isn't saying much as I haven't seen that many.

The only reason I have dry vents is more out of ignorance than anything as I've never attempted a total gut job of cast iron and galvanized plumbing. My piping is exactly as you show with green, blue, & red.

Ignorance is not bliss! If my response is correct it would sure save me a lot of headache.

 

[Hawk73ku]

Several comments based on the IPC:

- Your diagram is confusing because it appears you are attempting to show 3 dimensions on the page, without any guidance or system for which lines are actually vertical.

- In your picture, it appears you have a 3" drain line running through your joists. For the IRC, the largest prescriptively allowable hole diameter in a joist is 1/3 the joist depth. All holes need to avoid the top and bottom 2" of height of the joist. Holes in joists also must not have any notches above or below them.

If your joists were 2x12 (they look smaller) at 11.25" of depth, then you could drill a 3.75" hole through them for a 3.5" OD 3" DWV pipe, as long as that hole is in the central 7.25" of the joist height. But you have notches below your holes. So the joists with the 3" DWV passing through them will need to be repaired.

- For a bathroom, you always have to dry vent the lavatory (the highest trap in the room) with a vent through the roof or with an AAV. That vent needs to connect to the lavatory trap arm above the floor, within one trap diameter of fall from the trap outlet. Typically via a san-tee in the wall behind the lavatory. So do you have that?

Typically that is the only dry vent you need, as you can wet vent all the other fixtures. The diagram below shows just the underfloor drain piping you would then need, along with the minimum sizes, where green is 1.5", blue is 2", and red is 3". The green line from the vanity is the one that is dry vented above the floor. Note that the tub and the shower trap arms have to be "short enough", meaning that the trap arm may only fall one trap diameter before joining the drain that wet vents the fixture (the drain carrying the lavatory drainage).

- If for some reason you want to dry vent every fixture, let us know and we can answer the actual questions you posted in the OP.

Cheers, Wayne

View attachment 107525

You meant "drain line from vanity and tub".

I don't think your "shower vent" is needed, since the shower would be wet vented by the vanity.

That would take care of a big headache! I thought I needed it but couldn't get vertical with a T let alone trying to get a WYE in there. I'd be more than happy to dispose of it!

 

[Hawk73ku]

so there is no vent for the lav ? you didnt draw a vent for lav that vent upstream is a horrizontal dry vent below the floor as is the 2 inch vent is illegal under floor as both are dry vents

I hope what you call lav is what I call vanity and yes it is vented exactly as @wwhitney describes it should be.

 

[Hawk73ku]

You meant "drain line from vanity and tub".

I don't think your "shower vent" is needed, since the shower would be wet vented by the vanity.

You got me. FROM I've taken out vents for shower & tub so now I just have the vanity/lav vent as @wwhitney described should be and the diagram marked with green, blue, & red is exactly how the pipes are.

 

[Jeff H Young]

I hope what you call lav is what I call vanity and yes it is vented exactly as @wwhitney describes it should be.

I think you are good then I couldnt tell yesterday that the Lav (vanity ) was properly vented and there was a redundant vent next to it serving the tub looks good

 

[Hawk73ku]

I want to thank everyone that contributed to my edification. I'm less ignorant today thanks to your advice, in particular @wwhitney who provided detailed information in layman's terms. My blunder of not venting the toilet/WC led to adding that vent and removing air vents to shower and tub. I learned from you that the only air vent required was that of the vanity/lav and that tub and shower were wet vented which I came to understand uses the air from vanity and top half the drain pipe. So once again, THANK YOU VERY MUCH!